Drift Definition and 150 Threads

Homework Statement An aluminum wire with a diameter of 0.100 mm has a uniform electric field of 0.200 V/m imposed along its entire length. The temperature of the wire is 50.0 C. a) Determine resistivity b) Current density c) Total current d) Drift speed of the conduction electrons...

Homework Statement Estimate the mean drift velocity of a conduction electron in copper, assuming that there is one conduction electron per atom. Consider No. 14 wire (diamter 0.16 cm), common in houses, carrying 5A. The result should be very small. Why then does an electric light turn on...

For the last two+ years I've been involved in a project for a large company, that began as a back-of-a-napkin idea. I can't describe the project as it is all proprietary [customer] information, but the issue of scope drift is still interesting to consider. I will do my best not to be too...

Homework Statement Attached to my forum is my homework. I need help with #9 and #10. I have no clue on where to start. Anything is helpful Homework Equations The Attempt at a Solution

I was wondering if anyone knew the formulas uses to calculate the length and size and spacings of the drift tubes used in accelerators, and the formula used to calculate the frequency the tube is driven at. Edit, looks like I put this in the wrong section, hopefully someone can move it.

J_e=q\mu \bar{n}E-qD_e\frac{d\bar{n}}{dx} i can't understand this equation what each member of this equation i only know that \mu is the drift coefficient E is the field what the rest of the memebers represent ?

I'm teaching myself some physics, and I am having some difficulty with the concept of drift speed. My book derived the time between collisions using ma=Eq and then substituting the acceleration into the first equation of kinematics and solving for v(final) as the drift speed. The time it...

There is a belief that a complete interruption of the North Atlantic drift current could cause abrupt climate change. The amount of heat transported by the North Atlantic drift current and the Gulf stream is 8 times smaller than the amount of heat transported by the atmosphere transferring...

Homework Statement I’m trying to find the drift speed of electrons in a copper wire. The length of the wire is 10 meters, temp is 60°C, current is 5 A and the total resistance of the wire is 0.05 ohms. Homework Equations # of charge carriers (n) = density * 6.02 x 10^23/molar mass...

Homework Statement v=qEt/m t=time between each collision q=charge on particle m=mass of particle E=electric field Why is this the average velocity/drift speed in a conductor? Homework Equations The Attempt at a Solution Doesn't qEt/m = the final velocity of the...

Hi! I was just reading about drift speed and I read that the speed is about 10^-4m/s. It then struck me that if electricity is carried by electrons, then in a given circuit, how is the light bulb lighting up so quickly when according to my calculations the time taken to travel 0.5 metres for...

I would request for help in understanding why the drift speed of electrons in semiconductors is more than that of holes. Thanks.

Homework Statement A current of 200 mA flows in a silver wire of radius 0.8mm. Find (a) the drift speed of the electrons. (b) the number density of particles. Homework Equations The Attempt at a Solution The answer in the book is 1.07 x 10^-5, but I'm getting 1.06 x 10^-4. Can anyone tell me...

I'm using an opamp to amplify ac signals 40hz and up but there is still temperature drift, I thought drift was only a problem for dc signals? how do you get rid of temperature drift?

Homework Statement The figure shows wire section 1 of diameter 4R and wire section 2 of diameter 2R, connected by a tapered section. The wire is copper and carries a current. Assume that the current is uniformly distributed across any cross-sectional area through the wire's width. The electric...

Homework Statement A gold conductor with an electric field of 0.01 V/m applied, is 0.01 m long and 5.0E-5m in radius. Assuming one conduction electron per atom, what is the drift velocity of the electrons at a temperature of 20.0 degrees C? at 50 degrees C? Homework Equations I know that...

Homework Statement 1.0 * 10^20 electrons flow through a cross section of a 2.0-mm-diameter iron wire in 5.0 s. What is the electron drift speed? Homework Equations v_d = e*tao/m * E i_e = n_e * e * tao * A/m * E The Attempt at a Solution I can't seem to get very far. I think...

Homework Statement A. When current flows in an ionic solution, both negative and positive ions are charge carriers. In the dilute limit, the resistivity of the solution is inversely proportional to the concentration. For example, the resistivity of salt water solution at 25 °C is ρ =...

The electron drift velocity in a wire is about 0.1 mm/s. http://www.ac.wwu.edu/~vawter/PhysicsNet/Topics/DC-Current/Current.html If a coil were constructed from a helical nonconducting tube and filled with mercury such that if a current was passed through the mercury, a magnetic field would...

I'd be interested in any ideas or theories or references on how the location of the continents is thought to affect global warming and cooling cycles. I previously read somewhere that the current position of the continents would cause different net solar heat absorption/reflection than prior...

Homework Statement A thin metal film of length 1.00 cm, width of 0.250 cm, and thickness of 29.0 micrometers is used to measure the Hall effect. A current of 2.60 A is maintained along the length of the sample. The Hall voltage of 16.0 microVolts is detected across its width, when a magnetic...

Just hoping you might explain the physics here for me. An electron is placed in an oscillating electric field, say, E = E_0\sin(\omega t) and as a result accelerates in x at, a = a_0\sin(\omega t) (grouped some constants in a_0). Solving for the resulting motion yields, x =...

Homework Statement A piece of copper wire joins a piece of aluminum wire whose diameter is five times that of the copper. The same current flows in both wires. The density of conduction electrons in copper is 1.1 \times 1029 m-3 in aluminum it is 2.1\times1029 m-3. what is the drift speed...

Homework Statement A 150 km long high-voltage transmission line 2.0 cm in diameter carries a steady current of 1030 A. If the conductor is copper with a free charge density of 8.9 1028 electrons per cubic meter, how many years does it take one electron to travel the full length of the cable...

I realize a sample and hold is used in digital control whereby the circuit holds the analogue value steady for a short time while the converter or other following system performs some operation over that held time. However what does it mean by having low drift?

when talking about strain gauges, what does 'drift' refer to exactly?

[SOLVED] Determining current and drift speed Homework Statement http://img162.imageshack.us/img162/145/problemrg5.jpg The two wires in the above figure are made of the same material. What are the current and the electron drift speed in the 2.0mm-diameter segment of the wire. Homework...

[SOLVED] Another Current and Drift Velocity Question 1. A car's starter motor draws 50 A from the car's battery during startup. If the startup time is 1.5 s, how many electrons pass a given location in the circuit during that time? 3.As current = rate of flow of charge, I = q/t...

[SOLVED] Current and Drift Velocity (multiple choice) 1. In a dental X-ray machine, the movement of accelerated electrons is east. The current associated with these electrons is in what direction: (a) east, (b) west, or (c) zero? 3. At first I thought it was B (west) because...

Hello, I have found several overviews on the classical perihelion drift calculation from the planets perturbations. However, I could not identify what the best reference would be. I am -of course- interrested by those calculations that garantee a precision compatible with the discussion...

Homework Statement I am working on a problem and don't know if I am going about it right because I am stuck. A charged particle of mass m and positive charge q moves in uniform electric and magnetic fields, E pointing in the y direction and B in the z direction (an arrangement called "crossed...

I have looked all over in many textbooks and I cannot find a decent explanation of this. Most textbooks simply say that it is independent of applied bias because all of the minority carriers generated by thermal energy within a diffusion length of the depletion region will essentially get swept...

I'm really stuck on this one problem: "A small but measurable current of 4.20E-10 A exists in a copper wire whose diameter is 0.02 cm. Calculate the electron drift speed (in meters/second)." Source: Serway and Jewett I know that: I = 4.20E-10 A n = 8960 kg/m^3 q = 1.6E-19 C d = 2E-4...

Not sure if this should be in this forum, but let's try. The problem is about 2 samples. One pure Na and one InSb. I want to determine the hall voltage when we send a current of 100mA trough the samples and the magnetic field is B = 0.1T. The samples are dimensioned "squared" 5x1x5mm. We...

Homework Statement A 200-km-long high-voltage transmission line 2 cm in diameter carries a steady current of 1000 A. If the conductor is copper with a free charge density of 8.5 x 10^28 electrons per cubic meter, how many years does it take one electron to travel th full length of the cable...

In class today we talked about drift velocity and we measured it for a 14 gauge copper conductor wire. It came out to be 3.55 * 10^-3 cm/s. I was wondering if the speed is so slow, then how can light come on instanteneously when you flip the switch over long distances? Is it because there might...

Dear All, I would be interrested by reading some original paper on the classical evaluation of the advance of the perihelion. I found a few simplified models (see...

I think that in Special Relativity, the drift of the perihelion can be calculated by cumulating elementary Lorentz transformations along the (Newtonian, unperturbed) trajectory. I read that the result of this calculation is much smaller than the experimental value. It is also well known that...

For a fascinating and detailed Powerpoint Presentation of one research group's reconstruction of the changes in continental configuation around Antarctica over the last 200MA, go to http://www.ig.utexas.edu/research/projects/ant_cd/ant_cd.htm?PHPSESSID=def1b9 and click "Antarctica: Keystone of...

Question asks: A potential difference of 3.0V is applied to the ends of a copper wire which is 0.5m long. In copper at room temperature, the average time interval between collisions is \tau = 2.7*10^{-14}s. What is the drift velocity of the free electrons in the wire? Well, I know that...

In a circuit, if the voltage is doubled, what happens to the drift velocity?

If I move a strip of copper mechanically with my hand through a uniform magnetic field will their be a drift velocity? And if so will the drift velocity be in the same direction as the moving copper strip? What would the magnitude of the drift velocity be if this happens? Can you have a drift...

I was solving the following problem the following way: In a solid the atoms are regularly arranged in space. The potential seen by an electron is thus periodic and the energy levels are arranged in bands in which the energy of a state k is given by: ek= Eat + 2t cos(ka) The relevant...

I've got an understanding problem. It's about the behaviour of charged particles in plasma inside of a tokamak. It says that a particle in the non-homogeneous magnetic field (toroidal field), moving on the spiral trajectory all along the magnetic field lines, tends to drift downward (for...

Describe the process of simulating a brownian motion with drift of 4 units and diffusion of 2 units. write a program in any application to imulate such a brownian motion. Anyone knows where should i start first if i use excel to do it. I don't know what equation to use.

The electron drift speed in a gold wire is 3.0 * 10^-4. 1. What is the current density in the wire? 2. What is the current if the wire diameter is 0.50 mm? J = I / A and I = nqva What is the answer?

You are more likely to be killed by a pig than by a shark. – Biologist; The History Channel, Beach, Sun, 911 – 7/7/01 Your fingernails grow at about the same rate that continental drift occurs.

for a normal solid cylindrical resistor, made of say copper, at room temperature, describe the relationshop between the current in the conductor, the drift velocity of conduction electrons in the conductor, and the thermal velocity of conduction electrons in the conductor.

I don't even know where to begin on this one. SPEAR, a storage ring about 72.0 m in diamter at the Stanford Linear Accelorator, has a 20.0 A circulating beam of electrons that are moving at nearly the speed of light. How many electrons are in the beam? My thoughts, hmmmm. Nothing I can...

Test 3: Dual GPS one-way Lightspeed tests outside the LASOF area. The oscillating quantum vacuum frame will originate a difference in the (one way) light speed between two GPS satellites in space (up and down), measured parallel with the orbital propagation direction of the Earth around the...